Tunable Interlayer Excitons and Photoluminescence in Rare‐,Earth Dual‐Doped MoS₂ Homojunctions via Twist‐Angle‐Engineered Nanoarchitectonics

Abstract 2D transition metal dichalcogenides (TMDs) have received extensive attention due to their tunable electronic and optical properties. Trivalent rare earth ions doping can be used as luminescence activation centers to significantly improve their luminescence efficiency. Nevertheless, few studies are reported on the investigation of rare‐earth dual‐doped TMDs homojunctions. Herein, Er‐MoS 2 /Yb‐MoS 2 dual‐doped homojunctions with different twist angles are constructed by the mechanically transferred stacking. Unlike pure MoS 2 bilayers or other MoS 2 heterojunctions that suffer from photoluminescence (PL) quenching, the constructed dual‐doped MoS 2 homojunctions with specific twist angle exhibit a prominent PL peak with three‐fold increase of intensity and prolonged exciton lifetime. This unique behavior arises from the formation of localized interlayer excitons induced by two synergistic factors including rare‐earth doping modulating effect and specific stacking angle. The introduction of rare‐earth doping increases localized interlayer exciton formation in doped homojunctions and enhances the radiative recombination and exciton lifetimes. The precise control of stacking angles of doped‐MoS 2 homojunction can effectively modulate the interlayer coupling, enabling optimized conditions for exciton localization. This work establishes an efficient strategy to construct localized interlayer excitons in rare‐earth doped 2D materials for the junctions, but also provides fundamental insights into the design of high‐performance light‐emitting devices.